Potential effects on clinical management of treatment algorithms on the basis of apolipoprotein-B/A-1 and total/high-density lipoprotein-cholesterol ratios.

Background: Apolipoprotein-B/A-1 (apoB/A-R) and total/high-density lipoprotein-cholesterol ratios (TC/HDL-R) outperform non-high-density lipoprotein-cholesterol (non-HDL-C) suggested by Adult Treatment Panel (ATP) III guidelines for predicting cardiovascular (CV) outcomes.
Objective: To evaluate the potential effects that implementing our proposed apoB/A-R and TC/HDL-R treatment algorithms would have on clinical management.
Methods: We performed a chart review of all patients referred to the University of Michigan Lipid Clinic from January 2004 to June 2010. ATP III guidelines, including Framingham Risk Scores, were used to determine whether patients met non-HDL-C goals upon referral. Next, we evaluated whether subsequent management would differ if algorithms based upon potential apoB/A-R or TC/HDL-R targets derived from the literature were followed.
Results: Among patients (n = 692), mean non-HDL-C, apoB/A-R, and TC/HDL-R were 192.2 ± 85.8 mg/dL, 0.92 ± 0.64, and 6.7 ± 8.0, respectively. Although moderately well correlated with apoB (r = 0.56, P < .01), non-HDL-C was less related to apoB/A-R (r = 0.20, P < .01) and TC/HDL-R (r = 0.39, P < .01). Most low-risk patients (<2 risk factors; n = 207) at non-HDL-C goal (<190 mg/dL) also met apoB/A-R <0.9 (79%) and TC/HDL-R <6.0 (92%) targets. However, a minority of high-risk patients (Framingham Risk Score >20%, cardiovascular disease or risk equivalent; n = 307) meeting non-HDL-C goal (<130 mg/dL) achieved targets for apoB/A-R <0.5 (21%) or TC/HDL-C <3.5 (42%). The percentages of intermediate-risk patients meeting both non-HDL-C and ratio goals varied; nonetheless, few met an aggressive apoB/A-R <0.6 (36%-50%) target.
Conclusions: Most high- and many intermediate-risk patients at non-HDL-C goals would require more aggressive treatment to reach the suggested apoB/A-R or TC/HDL-R targets. Whether this strategy yields superior outcomes merits future investigation.
(Copyright © 2011 National Lipid Association. Published by Elsevier Inc. All rights reserved.)